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We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.

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Image courtesy NASA/JPL-Caltech/R. Hurt (SSC-Caltech)

New planetoid named Sedna discovered
News story originally written on March 17, 2004

Astronomers have found a new object in our Solar System. The new object is named Sedna. Astronomers are calling Sedna a "planetoid". A planetoid is smaller than a planet but bigger than asteroids or comets.

Sedna is very far from the Sun. Pluto is the farthest planet from the Sun. Sedna is more than twice as far away as Pluto. Sedna is 90 times as far from the Sun as Earth!

Sedna is very, very cold because it is so far from the Sun. Sedna takes a very long time to go around the Sun. One orbit takes more than 10,000 years!

Sedna is so cold that scientists decided to name it after something from the Arctic. Sedna is the name of the sea goddess in the myths of the Inuit people who live near the North Pole.

Last modified April 6, 2004 by Randy Russell.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA